Unusable area measurement in leather surface by image processing

• Main Authors: Lee-Jane Chen, 陳麗貞
• Other Authors: Der-Baau Perng
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/60452937547355449802

碩士 === 國立交通大學 === 工業工程與管理系 === 87 === In the first part of the study, we categorize the defects according to their shapes. There are seven categories：spots、thin spots、strips、irregulars、patterns、and holes. Because color and brightness are two important factors that will alter inspection results, so we take monochromatic and color images of each leather for experiments. For color images which are composed of RGB colors, every image may differ their reaction to color image processing. So three processing were used to process R、G、B colors separately and these three processings were integrated into one final result. The binarization method used in this study follows that of OTSU【1979】and Matrox Inspector. The comparison about these two binarization methods is also implemented. Only holes hold better inspection results in this study. Other inspection results of different shapes are not satisfactory by using the method mentioned in this study and need other post processing to obtain better inspection results. The second part of the study is to develop a defect-grouping algorithm which processes the leather image in vertical、horizontal、and diagonal directions. The procedure must have the image to be rotated from 0 to 44 degrees and have the defects to grouped, and have the image to be rotated back to original position. Finally the unrotated and integrated image is returned to complete the grouping task. The errors of final results are within ±10% and are similar to those made by human experts suggests that the proposed method is feasible for calculating the unusable leather surface.